Yah, use DHCP Reservation for your Laptop and your PC:

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Even if your Laptop is off, someone may be getting into your Wifi and using it. I always keep the log running and even on my system I have caught people in there, no idea how they got in. Finally I set it to that it won't allow anyone into the Router unless it's from a MAC Address I had cloned. That closed off whatever avenue they were using to get in.

It could be your Opera Browser, I don't use it, but it's a good browser. And it also me depend on network traffic in your immediate area.

Try lowering the amount of space used by it's Cache files if you can. Usually, most browsers depend on the settings in your IE Internet Tools 1st Property sheet, I set it to 50 MB total. And try Chrome or Firefox or even Safari 5.1.7 if need be.

Try each of those browsers for your stream use, see how each of them behave and use the best one, only for that purpose. That's why I have IE, Chrome, and Safari, I use them for different things.